[Goat Blower]

I don't like turning cranks anymore, the only one I've ever had a spun bearing on was a .010" under crank, renitrided and everything. Some people have had great luck with them.

A half-quart high isn't going to make any real difference except maybe a few horsepower at high rpm. A couple extra quarts will.

I have a hard time believing you could knock hard enough to spin a bearing without breaking a ring land or something else. I'd lean towards some sort of oil blockage to that bearing.